○ Human lifespan benefit: not established by the compiled studies. Included records: no healthy-aging lifespan RCT — human evidence is a randomized, placebo-controlled telomere length biomarker RCT (Salvador 2016) plus an immune biomarker study; telomere length is a contested biomarker and the trials carry a commercial conflict of interest

Two caveats govern every page on this site. (1) Telomere length is a contested aging biomarker — it is measured differently by different methods, varies between tissues, and "longer" is not straightforwardly "healthier"; changing a telomere-length or telomerase-activity number in a trial is not the same as slowing human aging. (2) Activating telomerase is not risk-free — telomerase expression is low in many differentiated normal tissues, while some normal proliferating cells can express it. Cancer can also use telomere maintenance; the included human records do not resolve long-term cancer risk from pharmacological activation. Tellingly, the FDA-approved telomerase inhibitor — imetelstat (RYTELO, 2024) — inhibits telomerase to treat cancer (lower-risk MDS), the opposite direction from the anti-aging "activation" narrative.

What it is

Class: Astragalus-derived telomerase activator (supplement)

Also known as: TA-65, cycloastragenol, TA-65MD

Relationship to telomere biology: TA-65 is a small-molecule telomerase activator, an improved formulation of cycloastragenol purified from Astragalus membranaceus. It is the most-studied human 'telomerase activator' supplement; its randomized human data measure telomere LENGTH (a contested biomarker), not any clinical or lifespan outcome.

Regulatory status

Sold as a dietary supplement by T.A. Sciences; not an approved drug and not approved for any anti-aging, longevity, or healthspan indication. Supplement status is a marketing pathway, NOT evidence of an aging benefit.

Commercial conflict-of-interest note. The pivotal TA-65 human data — the telomere-length RCT (Salvador 2016) and the earlier immune study (Harley 2011) — were authored by people with a direct commercial interest in the product. TA-65 is sold by T.A. Sciences; Calvin Harley (a TA-65 co-inventor/commercial proponent) and other T.A. Sciences–affiliated authors appear on those papers. This does not automatically invalidate the results, but it is a material conflict of interest for a supplement marketed on telomere claims. TeloiX has no relationship with T.A. Sciences.

Mechanism

Reported to modestly activate telomerase (TERT) and, in a 1-year RCT, to increase measured telomere length in the low-dose arm. Telomere length is a contested biomarker and activating telomerase raises a cancer-risk question. See /telomerase-tert-terc, /telomere-length-biomarker, and /telomerase-cancer-paradox.

Animal lifespan evidence

Animal lifespan evidence: none in this dataset

No animal lifespan study for TA-65 is included in this dataset. The human evidence is telomere-length biomarker data only.

This is separate from human lifespan evidence, which is none for every intervention on this site. A mouse lifespan result is not a human lifespan result, and a telomere change is not a lifespan result in either species.

Evidence — Human (randomized, placebo-controlled — biomarker) verify: source publication identified; see evidence and limitations

Species / population	117 relatively healthy CMV-positive adults aged 53–87 enrolled in Barcelona, Spain; 97 completed (52 placebo, 23 low-dose, 22 high-dose). Harley 2011 was an uncontrolled bundled program.
Exposure, route, schedule	Oral TA-65MD: 250 U/day (8 mg active ingredient) or 1000 U/day (32 mg), in cycles of 90 days intake followed by 14 days abstinence across one year.
Comparator / duration	Placebo-controlled, double-blind, randomized; 1-year duration.
Endpoint / numeric result	In the adjusted multilevel model, the low-dose versus placebo difference in change at 12 months was +530 ± 180 bp (p=0.005). This is not the raw within-arm increase: Table 1 median-length group averages changed +240 bp in low dose and −290 bp in placebo. High-dose between-group changes were not significant. Harley 2011 reported immune-cell changes in a bundled uncontrolled program, not isolated TA-65 effects.
What it did NOT establish	Both endpoints are contested biomarkers (telomere length; immune-cell subsets), not clinical outcomes. No healthy-aging, disease-outcome, or lifespan benefit is established, and the data carry a commercial conflict of interest.

Negative or null findings

High-dose between-group telomere changes were not significant in Salvador 2016. The +530 bp estimate is the adjusted low-dose/placebo difference in change, not an unadjusted within-arm increase.
The 2025 meta-analysis exists, but its included-study table conflicts with original study designs/interventions; do not treat its pooled efficacy/safety figures as validated.

The form used in the trials

A product-fact block, not a recommendation. It records the form the trials used and what they administered. TeloiX does not rank products, name a best one, suggest a dose, or claim an effect.

Amount used in the trials	Oral TA-65MD: 250 U/day (8 mg active ingredient) or 1000 U/day (32 mg), in cycles of 90 days intake followed by 14 days abstinence across one year.
Trial population	117 relatively healthy CMV-positive adults aged 53–87 enrolled in Barcelona, Spain; 97 completed (52 placebo, 23 low-dose, 22 high-dose). Harley 2011 was an uncontrolled bundled program.
Regulatory status	Sold as a dietary supplement by T.A. Sciences; not an approved drug and not approved for any anti-aging, longevity, or healthspan indication. Supplement status is a marketing pathway, NOT evidence of an aging benefit.

Read the conflict-of-interest note above before you buy. The human data on this compound were authored by people with a commercial interest in it.

Find TA-65 (cycloastragenol) on Amazon →

The search returns several variants. The trials used TA-65, the branded T.A. Sciences formulation of cycloastragenol used in the Salvador 2016 randomized trial. See the conflict-of-interest note on this page.

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TA-65 (cycloastragenol)